T-Mobile announced Wednesday that it's starting a new plan that will let anyone test an iPhone 5S for free for seven days.

You also get unlimited data for that time.

It's a way for T-Mobile to lure new customers to its network. After the seven-day trial, you can choose to switch to T-Mobile for good.

The fine print: You have to give T-Mobile your credit card number before the trial. If you don't return the iPhone, T-Mobile will charge you $700.

In addition to luring new customers, T-Mobile announced current customers will be able stream music for free. The carrier partnered with popular services like Spotify, Rdio, iTunes Radio, and Pandora for the offer. You can stream music from those services without it counting against your data plan.

Here's there press release:

To kick off Un-carrier 5.0, T-Mobile today introduced “T-Mobile Test Drive” and pioneered a new way to buy wireless in the U.S. With T-Mobile Test Drive, anyone can get an iPhone 5s and unlimited nationwide service to take T-Mobile’s network for a data-intensive, seven-day spin at no cost.

Starting June 23, people can sign up for T-Mobile Test Drive at www.t-mobile.com/testdrive. A few days later, they’ll receive an iPhone 5s and they can put T-Mobile’s data-strong network to the test for seven full days.